Drill.



F. R. WEATHERSBY.

WITNESSES DRILL.

APPLICATION FILED JUNE 16, 19131 Patented Mar. 9, 1915.

ATTORNEYS UNITED STATES PATENT OFFICE.

FRED RICHARD WEATHEBSBY, F HOUSTON, TEXAS.

DRILL.

To all whom it may concern:

I particularly to drills of the type suitable for earth boring, my more particular purpose being to provide an improved drill having means for ositively centering the drill before the main cutting edges thereof come into play so that the drill will he at all times guided in an accurate straight path. I

Reference is made to the accompanying drawing forming a part of this specification. and iii/which like letters indicate like parts.

Figure 1 is a side elevation showing one form of my improved drill. Fig. 2 is a side elevation of the same. Fig. 3 is an in verted plan of the mechanism shown in Figs. 1 and 2. Fig. 4 is a front elevation of a slightly different form of my improved drill.

The drill shank is shown at 5 and is provided with a pair of lugs 6 integral with it and extending from it in opposite directions. The drill shank is provided with a.

threaded portion 7 of large diameter and with a reduced threaded portion 8. The drill shank is further provided with water holes 9 extending through it in'a direction parallel with its eneral axis. The drill shank is also provi ed with a slot 10 which extend the full width of the drill shank in cluding the lugs 6. A cutter 11 having generally the form of a flat plate is rovided with cutting edges 12 and also with pilot blades 13, these parts being integral with the cutter. The cutter is fitted neatly into the slot 10. For the purpose of holding the cutter in position, I provide two bolts I4, each extending through the lugs 6 and also through holes in the cutter; Detachably fitted upon the bolts 14 are nuts 15. With this arrangement the lugs 6 brace the cutter and the bolts 14 not only hold the cutter but strengthen both the cutter and the lugs.- If it should happen that the lugs 6 become cracked. or otherwise injured, the bolts 14 are adapted to hold the parts in their ap proximate positions until the drill is withdrawn and the damage discovered. In order Specification of Letters Patent.

Applicatldn filed June 16, 1913. Serial No. 773,887.

- with a threaded Patented Mar. 9. 15

to remove the cutter. all that is necessary is to take off the nuts iii displace the bolts 14. the reverse operation being followed when the cutter is to be connected with the drill stern.

In the form shown in Fig. 4. the drill stein appears at 16 and. is .rovided with a slot 17. The drill stem is urther provided ortion E8 of large diameter and with a t .readed portion 19 of reduced diameter. The drill stem here shown is provided with water holes 2% extending axially through it. he cutter appears at 21 and is provided with and with pilot hiades Bolts 24 titted with nuts 25 extend through the drill stem 16 and through holes in the cutter Q1 The drill stem 16 is provided with re cesses 26 for holding the nuts or bolt heads. The form shown in Fig. i differs from that appearing in the other figures chiefly in the fact that the lugs 6 are not employed. Th1 formation of the cutter used in either is practically the same and shown provides the extensions'or pilothlades 13 and 23 as shown in Figs. '1 and 4 respectively, at the ends of the horizontal cutting edges l2 and 22 respectively. hose pilot blades or extensions are provide! "1th cutting edges in a line below or to 0" I1 5156 of the line of the main cutting edges so that in operation the pilot blades first come into play so as to center the drill before the main. cutting blades begin their action, and as the =lriliin process continues the drill will be gulded and maintained in a straight and no curate path.

In both forms of my invention the drill stem is provided with threaded portions of reduced diameter. The purpose of this arrangement is to enable the drill stem to he connected with either a large pipe or a small pipe in order to supply the drill with water as the drill is turned. With my improved of my invention.

I claim A drill r iznprising a flat cutter having oppositely beveled straight cutting edges extending horizontaliy from the center tolow the line of the first mentioned 'e'dgw of Ward the edges of the cutter, and extensions the cuttex: disposed at the outer ends of said horizontal cutting edges and at right angles thereto, FRED RICHARD WEATHERSBY' said extensions depending below said hori- Witnesses:

zontal edges and having oppositely dis- J. D, LONG, posed horizontal cutting edges in a line be- I. A. LYONS. 

